Note 7 - Investment Securities - Securities With Gross Unrealized Losses (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Securities available for sale, less than 12 months, fair value	$ 690,547	$ 4,696,851
Securities available for sale, less than 12 months, unrealized losses	6,817	34,876
Securities available for sale, 12 months or more, fair value	6,706,268	7,380,043
Securities available for sale, 12 months or more, unrealized losses	127,579	184,010
Securities available for sale, fair value	7,396,815	12,076,894
Securities available for sale, unrealized losses	134,396	218,886
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale, less than 12 months, fair value		1,831,305
Securities available for sale, less than 12 months, unrealized losses		9,610
Securities available for sale, 12 months or more, fair value	534,227	1,345,990
Securities available for sale, 12 months or more, unrealized losses	2,780	11,806
Securities available for sale, fair value	534,227	3,177,295
Securities available for sale, unrealized losses	2,780	21,416
Residential Mortgage Backed Securities [Member]
Securities available for sale, less than 12 months, fair value	690,547	2,865,546
Securities available for sale, less than 12 months, unrealized losses	6,817	25,266
Securities available for sale, 12 months or more, fair value	6,172,041	6,034,053
Securities available for sale, 12 months or more, unrealized losses	124,799	172,204
Securities available for sale, fair value	6,862,588	8,899,599
Securities available for sale, unrealized losses	$ 131,616	$ 197,470

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 5
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-Publisher FASB
-Name Accounting Standards Codification
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